Hello, Sara is absolutely correct, an infection is stress on the body, and any stress can certainly cause an elevation in blood sugars. This can happen in even non-diabetics but usually their insulin is working well enough to bring it down fairly quickly. If this continues, I would see you PCP and discuss what measures can be taken to help the bg level. Are you a diagnosed diabetic or pre-diabetic? You might want to have an A1C blood test to see exactly where you bg's stand if not.
Hello and welcome to MedHelp's forums. To answer your question, yes. Absolutely. Being sick and having an infection, being under stress all can increase blood sugar. Here is some information on that. https://www.webmd.com/diabetes/features/surprising-blood-sugar-swings#1 This is something you should discuss with your doctor and we hope you are feeling better very soon.